#include "array.h"

#include <blue/core/iterator.h>
#include <blue/core/stream.h>
#include <blue/object/array.h>
#include <blue/object/type.h>
#include <stdlib.h>
#include <string.h>

static void array_release(struct b_object *obj);
static void array_to_string(struct b_object *obj, struct b_stream *out);

static struct b_object_type array_type = {
	.t_flags = B_OBJECT_FUNDAMENTAL,
	.t_id = B_OBJECT_TYPE_ARRAY,
	.t_name = "corelib::array",
	.t_instance_size = sizeof(struct b_array),
	.t_release = array_release,
	.t_to_string = array_to_string,
};

struct b_array *b_array_create(void)
{
	struct b_array *array
		= (struct b_array *)b_object_type_instantiate(&array_type);
	if (!array) {
		return NULL;
	}

	return array;
}

struct b_array *b_array_create_with_values(
	struct b_object *const *values, size_t nr_values)
{
	struct b_array *array = b_array_create();
	if (!array) {
		return NULL;
	}

	size_t real_nr_values = 0;
	for (size_t i = 0; i < nr_values; i++) {
		if (values[i]) {
			real_nr_values++;
		}
	}

	array->ar_len = real_nr_values;
	array->ar_cap = real_nr_values;
	array->ar_data = calloc(real_nr_values, sizeof(struct b_object *));
	if (!array->ar_data) {
		b_array_release(array);
		return NULL;
	}

	size_t index = 0;
	for (size_t i = 0; i < nr_values; i++) {
		array->ar_data[index++] = b_retain(values[i]);
	}

	return array;
}

static b_status resize_array(struct b_array *array, size_t new_capacity)
{
	if (array->ar_cap < new_capacity) {
		void *new_data = realloc(
			array->ar_data, new_capacity * sizeof(struct b_object *));
		if (!new_data) {
			return B_ERR_NO_MEMORY;
		}

		array->ar_data = new_data;
	} else {
		for (size_t i = new_capacity; i < array->ar_len; i++) {
			b_release(array->ar_data[i]);
		}

		void *new_data = realloc(
			array->ar_data, new_capacity * sizeof(struct b_object *));
		if (!new_data) {
			return B_ERR_NO_MEMORY;
		}

		array->ar_data = new_data;
	}

	array->ar_cap = new_capacity;
	if (array->ar_len > new_capacity) {
		array->ar_len = new_capacity;
	}

	return B_SUCCESS;
}

b_status b_array_append(struct b_array *array, struct b_object *value)
{
	return b_array_insert(array, value, B_NPOS);
}

b_status b_array_prepend(struct b_array *array, struct b_object *value)
{
	return b_array_insert(array, value, 0);
}

b_status b_array_insert(struct b_array *array, struct b_object *value, size_t at)
{
	if (at == B_NPOS) {
		at = array->ar_len;
	}

	if (at > array->ar_len) {
		return B_ERR_OUT_OF_BOUNDS;
	}

	b_status status = B_SUCCESS;

	if (array->ar_len + 1 > array->ar_cap) {
		status = resize_array(array, array->ar_cap + 8);

		if (status != B_SUCCESS) {
			return status;
		}
	}

	struct b_object **src = array->ar_data + at;
	struct b_object **dest = src + 1;
	size_t move_len = (array->ar_len - at) * sizeof(struct b_object *);

	memmove(dest, src, move_len);

	array->ar_data[at] = b_retain(value);
	array->ar_len++;

	return B_SUCCESS;
}

b_status b_array_remove(struct b_array *array, size_t at)
{
	if (at >= array->ar_len) {
		return B_ERR_OUT_OF_BOUNDS;
	}

	struct b_object **src = array->ar_data + at;
	struct b_object **dest = src + 1;
	size_t move_len = array->ar_len * sizeof(struct b_object *);

	b_release(array->ar_data[at]);

	memmove(dest, src, move_len);

	array->ar_len--;

	return B_SUCCESS;
}

b_status b_array_remove_front(struct b_array *array)
{
	return b_array_remove(array, 0);
}

b_status b_array_remove_back(struct b_array *array)
{
	return b_array_remove(array, array->ar_len - 1);
}

struct b_object *b_array_pop(b_array *array, size_t at)
{
	if (at >= array->ar_len) {
		return NULL;
	}

	struct b_object **src = array->ar_data + at;
	struct b_object **dest = src + 1;
	size_t move_len = array->ar_len * sizeof(struct b_object *);

	struct b_object *out = array->ar_data[at];

	memmove(dest, src, move_len);

	array->ar_len--;

	return out;
}

struct b_object *b_array_pop_front(struct b_array *array)
{
	return b_array_pop(array, 0);
}

struct b_object *b_array_pop_back(struct b_array *array)
{
	return b_array_pop(array, array->ar_len - 1);
}

struct b_object *b_array_at(const struct b_array *array, size_t at)
{
	if (at >= array->ar_len) {
		return NULL;
	}

	return array->ar_data[at];
}

struct b_object *b_array_get(struct b_array *array, size_t at)
{
	if (at >= array->ar_len) {
		return NULL;
	}

	return b_retain(array->ar_data[at]);
}

size_t b_array_size(const struct b_array *array)
{
	return array->ar_len;
}

size_t b_array_capacity(const struct b_array *array)
{
	return array->ar_cap;
}

static void array_to_string(struct b_object *obj, struct b_stream *out)
{
	struct b_array *array = B_ARRAY(obj);

	if (!array->ar_len) {
		b_stream_write_string(out, "[]", NULL);
		return;
	}

	b_stream_write_string(out, "[\n", NULL);

	b_stream_push_indent(out, 1);
	size_t len = b_array_size(array);

	b_array_iterator it;
	b_array_foreach(&it, array)
	{
		bool is_string = b_typeid(it.value) == B_OBJECT_TYPE_STRING;

		if (is_string) {
			b_stream_write_char(out, '"');
		}

		b_to_string(it.value, out);

		if (is_string) {
			b_stream_write_char(out, '"');
		}

		if (it.i < len - 1) {
			b_stream_write_string(out, ",", NULL);
		}

		b_stream_write_char(out, '\n');
	}

	b_stream_pop_indent(out);
	b_stream_write_char(out, ']');
}

static void array_release(struct b_object *obj)
{
	struct b_array *array = B_ARRAY(obj);

	if (array->ar_data) {
		for (size_t i = 0; i < array->ar_len; i++) {
			b_release(array->ar_data[i]);
		}

		free(array->ar_data);
		array->ar_data = NULL;
	}
}

void b_array_clear(struct b_array *array)
{
	while (array->ar_len) {
		b_array_remove_back(array);
	}
}

static bool array_iterator_next(struct b_iterator *it)
{
	return b_array_iterator_next((struct b_array_iterator *)it);
}

static b_status array_iterator_erase(struct b_iterator *it)
{
	return b_array_iterator_erase((struct b_array_iterator *)it);
}

static bool array_iterator_is_valid(const struct b_iterator *it)
{
	return b_array_iterator_is_valid((const struct b_array_iterator *)it);
}

static b_iterator_ops it_ops = {
	.it_next = array_iterator_next,
	.it_close = NULL,
	.it_erase = array_iterator_erase,
	.it_is_valid = array_iterator_is_valid,
};

int b_array_iterator_begin(struct b_array *array, struct b_array_iterator *it)
{
	it->_a = array;
	it->i = 0;
	it->_base.it_ops = &it_ops;

	if (array->ar_len > 0) {
		it->value = array->ar_data[0];
	} else {
		it->value = NULL;
	}

	return 0;
}

bool b_array_iterator_next(struct b_array_iterator *it)
{
	struct b_array *array = it->_a;

	if (it->value == NULL || it->i >= array->ar_len) {
		return false;
	}

	it->i++;

	if (it->i >= array->ar_len) {
		it->value = NULL;
	} else {
		it->value = array->ar_data[it->i];
	}

	return it->value != NULL;
}

b_status b_array_iterator_erase(struct b_array_iterator *it)
{
	struct b_array *array = it->_a;
	if (it->i >= array->ar_len) {
		return B_ERR_OUT_OF_BOUNDS;
	}

	if (array->ar_data[it->i] != it->value) {
		return B_ERR_BAD_STATE;
	}

	b_array_remove(array, it->i);

	if (it->i < array->ar_len) {
		it->value = array->ar_data[it->i];
	} else {
		it->value = NULL;
	}

	return B_SUCCESS;
}

bool b_array_iterator_is_valid(const struct b_array_iterator *it)
{
	struct b_array *array = it->_a;
	if (it->i >= array->ar_len) {
		return false;
	}

	if (array->ar_data[it->i] != it->value) {
		return false;
	}

	return it->value != NULL;
}

b_object_type_id b_array_type_id(void)
{
	return (b_object_type_id)&array_type;
}